We think of ourselves as a global species, but in fact we can only comfortably survive on less than a quarter of the earth’s surface. In To Boldly Go, doctor of extreme medicine Kevin Fong sets out to discover how we are able to conquer the other 75 per cent. In an eye-popping series of experiments, Dr Fong uses his own body to demonstrate how unsuited our biology is to much of the planet – and how we have had to develop the technology to let us survive there. Doctor Fong investigates how the human body can survive underwater, and how the body responds to altitude.